甲烷氧化偶联MgO／BaCO3催化剂的表面结构与催化活性

用ＣＯ２－ＴＰＤ，ＣＯ，ＣＨ４脉冲以及ＥＰＲ，ＸＰＳ等方法对ＭｇＯ／ＢａＣＯ３的表面结构及催化活性进行研究，结果表明，催化剂的碱性，氧扩散速率等对催化剂的活性均有影响。ＢａＣＯ３和ＭｇＯ的共同作用可以增强催化剂的碱性强度?增加强碱中心的量，调变晶格氧的移动性，提高Ｃ２烃的收率和选择性。ＥＰＲ和ＸＰＳ测试结果表明，表面吸附态的氧物种Ｏ＾－２作为甲烷氧化偶联活性氧物种的前驱态在反应反应条件下可转化为活

The Surface Structure and Catalytic Properties of MgO/BaCO_3 Catalyst for Oxidative Coupling of Methane

The catalytic performance and surface properties of the MgO/ BaCO3 catalyst were studied using catalytic activity testing and pulse reaction techniques, EPR and XPS methods.It was demonstrated that both the lattice oxygen mobility and Surface basicity affected the performance of the catalyst. The cooperation of BaCO3 with MgO resulted in the strong surface basicity and proper lattice oxygen mobility on the catalyst to favor the title reaction. EPR and XPS characterization indicated that the O2-ions as the precuresor of active species could be converted to O2(2-) ions, which are responsible for the methane activation. The activity of MgO, the active components of which could be adjusted by the cooperation of BaCO3, an inert component, to favor the title reaction, elevate both CH4 conversion and C2 selectivity.